XX1 knocking/clunking

I am experieriencing a knocking or clunking issue with my nearly new(90 miles) XX1 derailleur. The clutch clunks loudly when it engages as the bike goes through its travel. It feels and sounds like a locked up seat stay/swingarm bearing. With the wheel removed, when pushing the cage through its swing I can feel it clunk as it engages...so it likely has nothing to do with chain tension as mentioned here: Type 2 Derailleur "Knocking"

I have a brand new one to compare my semi new one and while it swings ok now I can feel hesitation in the beginning and is likely to have the same issue.

Any ideas? Anyone else experiencing this on XX1?

I semi-solved the issue by soaking the cage attachment area in dumond liquid lube.

It still makes noise and clunks while stationary and cycling the suspension but not while in motion on the bike.

SRAM: please pipe in here... What causes the clunking? Is it "normal" or is it something that needs to be returned for warranty? Is it a set up issue?(aka user error?)

Still clunkin

Hmm... and you can actually hear this while riding? I've got about three months of pretty hard use on my XO Type 2 (mid-cage) and I have noticed the klunking or lite knocking sensation when cycling the suspension at a standstill, but all I notice while riding is blissful silence.

If it's something you can hear over the noise of flying dirt/debris, etc. then perhaps there is something wrong, or maybe it's a function of clutch break-in and it'll get better with use? Or maybe it's an early-run XX1 quirk? Sorry I can't help with your case, but I would caution against fixating on it. Like I say if it's truly something you hear WHILE riding you may have an issue, though based on my own background of 'fixing' noises I'd say you may have created the creaking yourself by soaking the part in lube. Many modern bearing surfaces are designed to 'self-lubricate' with use and applying oils/solvents/thinning agents, etc. can often defeat the purpose. The knocking sensation when stationary is normal for a friction clutch-type tensioner but you'd be very hard-pressed to notice it while riding, as you said; however, the squeak is not something I've ever heard. If you don't have easy access to SRAM warranty I'd suggest cleaning it up as best possible with a simple rag, maybe a bit of iso alcohol or window cleaner... something to remove any excess lube that may be oozing out. Even better maybe use a soft brush and/or compressed air to clean up the pivot/clutch area. Then ride it, as much and as often as possible. As counter-intuitive as it sounds, many creak-type noise complaints can solve themselves with use, just a matter of components self-clearancing, if that makes sense?

Keep us posted if you don't mind, I'm planning on upgrading one of my bikes w/ XX1 as soon as I can find a buyer for a one-owner, lightly-used kidney.

There is no squeaking... More like a creak like the sound of a door with a hinge that needs lube. Admittedly, I only notice it while climbing, aka the time I have to dwell on things.. I can also feel it as the "clunk" reverberates through the seat stay.

My main question for SRAM: Is this noise and clunking normal?
It doesn't seem so as it functioned noiselessly for at least 7 rides...about 100 miles.

Ah so, didn't factor the 'climb fixation' into the equation... say no more, I live in NorCal, home of the Endless Fireroad Climb; I understand having blank mind space invaded by outside annoyances all too well. That's where I was coming from with my 'leave it alone and see if it goes away' advise - the pivots on my Type II-equipped bike are prone to creaking loudly (early GT Force) and it used to drive me absolutely mad, especially while climbing, to the point where I tried soaking things in lube as you have. I finally found a fix for that noise which involved (amongst other things) allowing the pivots to seat-in a bit. However, that's a totally different type of pivot interface than the friction clutch in your derailleur, obviously.

Interesting what you say about feeling the klunk too. My I-Drive frame has minimal chain growth throughout its travel so I really can't feel that slight play (klunk) at the beginning of clutch engagement unless I'm bouncing it while standing still. Even then it's very slight and feels more like my rear shock is due for service, which it is. But a suspension system with more pronounced chain growth (a la DW/VPP) could certainly exaggerate the sensation, especially if it's made of hollow carbon fiber.

Hopefully someone from SRAM or at least another XX1 user with some mileage will chime in with a fix, suggestion, or at least similar experience. Staying tuned...

Yep, started experiencing it after a really rainy ride. Was worse, got a bit better after I sprayed some WD-40 into the clutch-joint through the edges. But on a fully unlocked rear suspension the clack sound and a significant vibration are still there.

Would send it back for warranty replacement but don't want to pause my riding until I receive a new one (would take at least a month to where I live), so I guess I first have to get one extra. (Good to have one as a spare, right?).

Not making that part serviceable is a huge design oversight in my opinion, especially after so many reports of this Type 2 issue. This totally looks like a problem solvable by adding a small amount of grease - if you could access it.

Also the chain length has absolutely nothing to do with it - the clutch is supposed to move smoothly inside the whole radius it covers.

Maybe when I get the new one, instead of sending this one to warranty, I will rip it open to see if it's serviceable and possible to close again - will let you know.

I have had xx1 since December as well as a friend of mine, and we have not had a single issue or noise with it? I know this doesn't help you but maybe it's an isolated issue?

It is isolated (I assume you have seen the other about 5 threads about this here and on other sites - these include other Type 2's - X9, XO, XX), but it appears to happen after a dirt gets into the clutch joint of the derailleur, usually carried in there by water.

So it's either a manufacture defect which makes some of the products more susceptible to this kind of malfunction (which I seriously doubt given today's manufacturing standards - basically the only variable is material failure), or every single product is susceptible and will start doing this after e.g. a proper rainy ride. Read: it can happen to you.

It's also possible that the self-greasing mechanism the clutch is said to have is doing its job, but in this case a bit slower than it should (it's understandable that it needs to work slow in order to keep working for a very long time). In fact, the clack I have now is much quieter than the one on the video I posted, and I doubt the reason for that is that I tried to spray the thing with WD-40 from outside.

So it may be a good idea to try to cycle it by hand for a good 5 minutes, over its complete path of movement - back and forth - in the hope that the self-greasing mechanism will kick in faster.

Anybody heard from SRAM yet. Is the knocking a warranty issue they are taking care of? I was thinking of pulling the trigger on the whole XX1 group for a Jet 9 RDO I'm building. Then I decided I should do a Google search and found this thread Not suprised, but disappointed because the group is so simple and light.

Anybody heard from SRAM yet. Is the knocking a warranty issue they are taking care of? I was thinking of pulling the trigger on the whole XX1 group for a Jet 9 RDO I'm building. Then I decided I should do a Google search and found this thread Not suprised, but disappointed because the group is so simple and light.

I guess if you don't plan on riding in really rainy / wet conditions, then there is not a big risk of this happening to you. (That of course is an assumption in and on itself.)

I think some of the X9/XX/XO Type 2 guys got this replaced under warranty, I think I've seen at least one such report. (Not sure if that was easier because the LBS did it for them, better check those threads yourself.)

In my opinion the XX1 is very much worth it despite this flaw / the risk of this flaw happening to you.

I have about 60 miles on mine and it started to clunk today. It has not gotten wet and have only ridden in the dry. I thought it was something in the rear suspension and then realized it was my new XX1. Guess I will call Sram next week to try and get some answers. It has pink stuff around the clutch which Sram said was ok.

Hey guy's,
I did a little experimenting with my X9 type 2 rear derailleur today trying to eliminate the clunking. Here is what I did and it completely resolved the clunking issue. What I found is the roller bearing was completely dry of grease. I'm not the most detail oriented guy so if you have any questions feel free to PM me with your number and I can walk you thru the steps over the phone.

Here is a quick DIY on what I did:

-Remove rear derailleur from bike

-On the outside of the RD were the clutch is there is a small plastic cap. Pry the small plastic cap off and it will expose a T55 torque bolt. The is the bolt that says ( type 2 roller clutch) on it. Remove that torque bolt.

-Remove the outer cage (3mm allen) and pulleys.

-From there you will see another 3mm allen bolt at the top of the RD. Remove it carefully as the inner cage is under pressure from the RD return spring. I held the RD body and inner cage together with my hand while removing the 3mm allen.

-Once the bolt is removed pull and inner cage is off pull out the RD return spring and set it aside. The is only one way it can go back in so don't worry that.

-Once the spring is removed press the center of the clutch mechanism out to the other side of the RD. I screwed the 3mm cage bolt back in the hole and taped on it lightly with a hammer to get it to pop out the other side.

-From there you will see the shaft with a plastic sleeve on it. (That's the roller bearing)

-Slide the roller bearing off and grease the shaft, roller bearing's and outer plastic sleeve. Also grease the back side of the T55 torque bolt and the plastic spring guide that sits on the inner cage.

sounds great! it actually stopped to bother me for some reason, but if there's a lack of grease then i guess i have to put some in to prevent premature wear.

one question though - now when you cycle the derailleur by hand when mounted on the bike, do you find the clutch resistance the same as before? (except the extra resistance spike on the beginning of the movement which was there previously due to the lack of grease.) or to put the question differently - do you find the resistance adequate to prevent chain slap?

another question - the plastic cap you had to pry off - was that glued on? did you have to glue it back on? if yes, what glue have you used?

Thanks for the DIY. The sound I hear does sounds like dry parts rubbing together and is coming from the clutch. I will contact Sram first since I have only used the part for a week to see what they say. The clutch cap on mine has pink stuff around it and is not flush sticking out about 1/16. It looks like it has threads on it.

The pink stuff is lock tight. That's the cap you will pulling off with the T55 torque socket. If you tighten that cap down to much it puts more drag on the clutch action.

Thanks for your help. I see the little plastic cap comes off to expose the T55 screw on cap. How did you know when to stop tightening it (when the clutch felt resistance)? Mine already has a couple threads exposed when new, so I guess a torque is specified or some kind of resistance setting.

I was kinda lazy (needed to do this quick) to remove the chain and the derailleur and then put it back and recalibrate it etc., was quicker to just do it on the bike, although putting the spring back and preloading it with one rotation was quite an exercise (in fact probably the hardest bike mechanic operation I've done by far). (I did separate the derailleur from the bike, but did not separate it from the wire.)

At first I just undid the T55 torx, tilted the bike and drowned the clutch in WD40, but that did not help. The WD40 has made into the roller bearing (as I found when I opened it), so my hunch is that it's not the roller bearing that was the problem, but something external to it (but internal to the derailleur clutch joint).

So I greased everything, cycled the cage by hand properly, and then tightened the T55 to a level where no chain slap is possible, yet the derailleur cage moves smoothly.

I CAN NOT BELIEVE the difference this has made:
1. on the ease and precision of the shifting,
2. on the increased smoothness of the rear suspension.

Of course the bad sound went away too, but the bad sound was nothing compared to the other 2 points.

Should I get a new XX1 rear derailleur in the future, you know what's the first thing I'm doing with it, clacking or not.

I called SRAM because I'm having the same issue with my XX1 derailleur on a new Blur TRc that I just built up. Basically, the rep said that the knocking should get better once I break in the derailleur, but that it is also "a function of the Type 2 derailleur."

Both of these statements seem odd since some people aren't having this issue at all and some people are having this issue after the derailleur has been ridden some. Some of the problems could be from user error I guess or based on suspension design. Nonetheless, it would be nice if this fancy system didn't have this issue.

I haven't ridden the bike yet, so my hope is that the knocking sound either won't be noticeable or will go away on trails. If not, I'll try adding a couple of links (even though I'm fairly certain the chain is properly sized). If that doesn't work I'll see if SRAM can warranty it or else open up the derailleur...not motivated enough yet to open up a brand new derailleur.

...Basically, the rep said that the knocking should get better once I break in the derailleur, but that it is also "a function of the Type 2 derailleur."...

My experience is that it only gets worse with time, plus the extra strain put on the derailleur due to the clutch not working smoothly actually wears the derailleur much faster. Mine started to squeak also on other places than the clutch joint, due to the extreme force the jammed clutch was exerting on it during rear suspension flexing.

It's also possible that all you need to do is to rotate the T55 (freely accessible under a non-glued removable plastic cover; but itself glued with a lock-tite) just a few degrees CCW, to make the clutch work with less resistance, as I reckon mine was way overtightened, and that may have been the cause of it all. If you remove the T55, you can also put some oil in, without removing the derailleur from the bike, or separating the cage at all. Whether this voids the warranty is another matter entirely.

I greased mine and so much better. Hopefully it will stay that way. Really disappointed in SRAM. I called to get the problem fixed after a couple of rides and they said take it to a dealer. I tried to buy the kit from my dealer, but they could not get it for 30 days so I bought it online. I did not feel right taking it to the dealer to get a warranty when Sram could have sent me the part.

The part I dont quite get is
"Wind clutch up and lock with pin and install lock bolt"

Is this what tightens the spring? Right now I have it all back together without the T55 in and the cage just swings around loose with no tension at all.

I believe you have to preload the spring once, meaning get the spring in the grooves for it and spin around the jockey/cage. It's a pain in the ass, but it's doable.

When I did this, the wheel was off the bike and the jockey/cage was apart from the rest of the derailleur, and the chain was off the derailleur as well. I reinstalled jockey/cage with the 3mm bolt just enough to keep things from flying apart before winding up the spring (that helps keep the parts in place until you tighten down the bolt). Once you spin around the jockey/cage so that the little cylindrical part goes past the groove in the upper part of the derailleur, tighten down the 3/4mm bolts. I got someone to help me tighten down the bolt so I could focus on keeping the spring preloaded...Sorry, wish I knew what all the parts were called.

For what it's worth, I opened up the derailleur and lubed up everything as suggested, but the knocking, while it goes away for a bit, comes back fairly quickly. It seems like the bolts tighten as the derailleur moves. It also seemed like just loosening the 3 and 4mm bolts and the T55 a bit is what made the derailleur stop making noise more so than putting oil in it. Also, I used a sewing needle to pry off the plastic cap that covers the T55, which kept the part intact.

I believe you have to preload the spring once, meaning get the spring in the grooves for it and spin around the jockey/cage. It's a pain in the ass, but it's doable.

When I did this, the wheel was off the bike and the jockey/cage was apart from the rest of the derailleur, and the chain was off the derailleur as well. I reinstalled jockey/cage with the 3mm bolt just enough to keep things from flying apart before winding up the spring (that helps keep the parts in place until you tighten down the bolt). Once you spin around the jockey/cage so that the little cylindrical part goes past the groove in the upper part of the derailleur, tighten down the 3/4mm bolts. I got someone to help me tighten down the bolt so I could focus on keeping the spring preloaded...Sorry, wish I knew what all the parts were called.

For what it's worth, I opened up the derailleur and lubed up everything as suggested, but the knocking, while it goes away for a bit, comes back fairly quickly. It seems like the bolts tighten as the derailleur moves. It also seemed like just loosening the 3 and 4mm bolts and the T55 a bit is what made the derailleur stop making noise more so than putting oil in it. Also, I used a sewing needle to pry off the plastic cap that covers the T55, which kept the part intact.

Yes you have to wind up the jockey. The bolt in the jockey I was talking about taking out is what you are calling the cylindrical part which screws into the jockey to keep the jockey from spinning around. The way I did it was to use the jockey lock to hold the jockey while removing the stop bolt cylindrical then unwinding the jockey. Then take everything apart grease and put back together. After you have it back together wind up the jockey and use the lock to hold it while you put the stop bolt cylindrical back in. It is very easy using the lock to hold the jockey while it is under load. I think the part you are missing is removing the stop bolt cylindrical on the jockey to let it unwind and wind.

The part I dont quite get is
"Wind clutch up and lock with pin and install lock bolt"

Is this what tightens the spring? Right now I have it all back together without the T55 in and the cage just swings around loose with no tension at all.

You need to take out the jockey stop bolt which is a small looking cylindrical bolt with a allen head and then wind up the jockey and lock it with the lock button and then put the stop bolt back in then release the lock. The spring does go in a slot on the derailleur and in a hole on the jockey plate.

Ever since I heard of this clutch design a while ago I wondered how the heck they would address chain growth issues. Anyone with issues on a HT? It just seems like someone in some department would have seen this coming..I did and I'm a plumber..

I took my bike to my LBS and it was a snap to get it back together. I removed the jockey stop bolt, got the spring into place and we wound it up basically 1 full rotation. tightened everything up and set the t55 bolt close to where it was stock. The knocking is gone now and shifting does feel a little crisper. Not sure how long it will last, but now that I know what to do i dont mind servicing the parts on a regular basis. Here in the PNW we do a lot of wet/muddy rides, so every 3-4 months i tear down my bike and clear/grease it all anyway.

your post was spot on. For anyone with knocking noise i would just remove the t55, add a little grease and then tighten the t55 to a point where the knock is gone but the clutch engages. Even just backing off the t55 a tad might be the best solution.

Thanks to everyone who was willing to mess with a $300+ bike part and post up info to the rest of us!

I know it's only been a couple of weeks for some of you guys, but how is the FIX working out. I'm thinking of getting a clutch derailleur, but I'm on the fence with brands. I currently have a new XO 10spd system and would like to keep my shifters, but will jump ship if I have to.

So I've helped quite a few people "cure" the clunk. We have been removing the t55, adding a little grease and then loosening the 3mm and 4mm bolts until you get the desired spot between no tension and clunking. I dont think taking it all the way apart is really needed.

I have noticed that while the 3mm stays in place (outside derailleur), the 4mm (under t55) seems to move a little. I suspect that over time that bolt is tightening and adding too much resistance which causes the clunk. I may try adding a washer to see if that will help keep the bolt from self-tightening.

So it sounds like your taking a tiny bit of resistance out of the system. Have you tried adding lock tight to that 4mm bolt. I've never had an opportunity to play with Srams of Shimano's derailleur. After you've reached the sweet spot how much tension is still in the system. My goal is to remove my MRP Micro chain guide and add a clutch derailleur in it's place. The chain guide does a great job of eliminating some of chain slap, but I find the roller to be noisy.

You basically can tighten and loosen that 4mm to any amount you want. I have been backing it off until it is silent when you pull the chain up toward the chainstay. The suspensions feels smoother, the noise and gone and I have had any chain slap issues so it still ahve plenty of tension to keep the chain under control. That's without any sort of guide either.

I know it's only been a couple of weeks for some of you guys, but how is the FIX working out. I'm thinking of getting a clutch derailleur, but I'm on the fence with brands. I currently have a new XO 10spd system and would like to keep my shifters, but will jump ship if I have to.

The noise on mine came back shortly after the "fix," I think because (as Mr. Lynch noted) the bolt tightens over time. I really don't notice the noise going dh, and only some times notice it while climbing, so I'm just go leave good enough alone. I still think the system is pretty awesome and would get it again.

if someone can shot a video the next time they grease one of these derailleurs that would be greatly appreciated. i want to grease mine up, but i having a bit of difficulty following along how to do it without a video.

if someone can shot a video the next time they grease one of these derailleurs that would be greatly appreciated. i want to grease mine up, but i having a bit of difficulty following along how to do it without a video.

Thanks for sharing this DIY. I was a bit worried opening this up because of the spring tension from reading this thread but to those of you that plan on doing this fix. It only took me just about 20 mins. It was really easy and the spring was easy to put on. Just screw in the 3mm bolt first (of course not all the way), just enough for you to still be able to wind the spring using the first part of the cage as a leverage.

Anyway, I greased everything inside even the spring! The result is super smooth suspension and the annoying knocking is gone!

Fyi.. Mine is the Type 2 X9 and it did have grease (brown in color) inside the bearing but very little. Even on the spring it has grease but thick grease. I used slick honey.

Just got my xx1 on my yeti sb 66 c and it does the same clunking noise. Calling sram tomorrow. This is brand new out of the box. We should not be having problems like this.

go get them, by all means. although the structure of today's megacorps is such that your feedback never makes it to the designer guy, who, i seriously doubt even reads forums like this one.
otherwise we would not be having these silly issues, with a part supposedly "non-serviceable".
heck i don't think they are even aware of this problem, which would be a thousand times better alternative than that they are aware, but don't do anything about it.

mine hasn't clunked since i greased it, but the smoothness decreased over time, and a new greasing would be good to do.

SRAM, just please make a few holes on the new one so that we can grease it without opening it.
SRAM, don't be ashamed that your derailleur needs greasing, it's kinda normal in the bike world.

I called and they said to take it to a bike shop. I did not feel right having the bike shop spend time on it after I bought it online. I tried to buy it from the bike shop, but had to wait 4 weeks. Another local rider already had his replaced for the knocking. Sram has also changed the chain design.

So I called sram and they are aware of the issue. They did say take it to the bike shop and have them call us. They also said they are still working out some bugs. That's kinda bull shit seeing that its been tested and has been available for how long now. I did ask them if I just need to take it apart and grease it and they said it would void the warranty if I did that. So guess I'm returning it and hope the next one is better than the first.

I have been enduring the knocking for a few months now on my SB66c because the XX1 was outta stock. I was contemplating opening up the clutch and greasing it but held back because it was still under warranty. Finally my LBS told me to bring it in as the new stocks had arrived. So, I will be sending it in to have SRAM tech ppl check it. If confirmed faulty, I will be getting a replacement. I just hope the new batch won't have this same problem.

the thing is, to remedy the clunking, in most cases you don't need to open it, and instead just loosen the big torx screw a little bit (like half rotation or something like that) - and that should not void the warranty in the slightest - imho.

the thing is, to remedy the clunking, in most cases you don't need to open it, and instead just loosen the big torx screw a little bit (like half rotation or something like that) - and that should not void the warranty in the slightest - imho.

i ride with the plastic cap removed actually, you can see the screw here:

using this screw, you are creating pressure on the clutch (you press the two parts of the clutch into each other), which affects how much initial resistance the clutch exerts in the direction made by the derailleur when the chain extends.

What! Everyone's out riding? Still would like to know of updates on the clutch. Also, if you have had a replacement from SRAM, did it take care of the issue?

yes i reckon somebody around here has mentioned that the problem came back after a replacement - well it's to be expected i think - there are conditions/environments (e.g. too wet rides), which make this more prone to happen.

the bad thing is, when the clacking sound is made, it also means that your derailleur body and the hanger (and possibly chainstay) are very stressed - you can actually observe them bending badly if e.g. you have somebody else to cycle your rear suspension while at standstill, and you observe it from up close.

using this screw, you are creating pressure on the clutch (you press the two parts of the clutch into each other), which affects how much initial resistance the clutch exerts in the direction made by the derailleur when the chain extends.

so just try to ease that up a bit and see.

This is the first thing I did on the RD. Loosen up the T55 screw and it didn't do anything. I then took the T55 screw off and compress the suspension (push down on the saddle to compress the suspension/chain growth) and the knocking was still there. Took the RD apart (as mentioned on previous post) and grease the everything where the clutch is. Knocking was eliminated but tension is still there. I have not dropped a chain or heard the knocking again. SUPER SMOOTH Shifting as well!!

On 4 different bikes with clunking issues (stumpjumper -xx1, Enduro -xx1, Demo -x9, and a Blur Lt- x0) I popped the t55 off, loosened the 4mm/3mm bolt until the clunk stopped, added a little grease into the opening and put the t55 back into place. None of the bikes have developed the clunk again.

the bad thing is, when the clacking sound is made, it also means that your derailleur body and the hanger (and possibly chainstay) are very stressed - you can actually observe them bending badly if e.g. you have somebody else to cycle your rear suspension while at standstill, and you observe it from up close.

Thanks, THAT is the reason I've become paranoid about the clunk. If SRAM could guarantee that the jockey wheels/chain/cassette would not see shortened life I might live with the clunk, but I doubt they would or could. As an engineer, I cant see how this would not shorten the life to some extent. I also have some shifting delays going down the cassette (low to high), which is more annoying than the clunk.
I am not afraid to dig into the RD, but would not want the warranty voided, so I'm in limbo until this somehow get's sorted out.

On 4 different bikes with clunking issues (stumpjumper -xx1, Enduro -xx1, Demo -x9, and a Blur Lt- x0) I popped the t55 off, loosened the 4mm/3mm bolt until the clunk stopped, added a little grease into the opening and put the t55 back into place. None of the bikes have developed the clunk again.

loosening my T55 about 1/2 turn and cleaning/greasing the derailleur hanger has seemed to have solved my problem. Have about 250 on it since.

If we knew exactly how the resistance is applied, then we would know how to reduce it. It's a pretty crude system that would use screw torque (T55 ?) to increase resistance, but maybe that's how it works. I wonder what role, if any, the 3&4 mm screws play.

What I am feeling when I move the derailleur forward is classic stiction. Force increasing until it releases (clunk/knock), then moves smoothly until forward motion stops. In this system, somehow you have to generate resistance either thru friction or force. Some material interfaces do a better job of minimizing stiction than others. OK, stop me from rambling.

What's the status on this junk? I have 10 miles on my new derailleur and it has started making noise

I've had two tech's look at mine. The last one loosened the T55 slightly and it did make a slight difference, and the shifting improved somewhat, but the clunk is still there.
I'm headed back in to have it warranted soon. Clearly a design flaw, which is uncalled for in a $400 simple mechanism.

I've had two tech's look at mine. The last one loosened the T55 slightly and it did make a slight difference, and the shifting improved somewhat, but the clunk is still there.
I'm headed back in to have it warranted soon. Clearly a design flaw, which is uncalled for in a $400 simple mechanism.

Oh boy! I'm excited to take it apart and mess with it I bought mine from a online store on eBay. Chances are SRAM won't warranty and I don't want to go through the store I got it from. Turn around times are probably ridiculous. Should have stuck with my 2x10

The 3/4mm bolts are what tensions the clutch. You can crank them tight and nearly lockout the RD, or you can open them way up and make it feel like a non-clutch RD. It is actually a very simple design and easy to adjust. When I took my Enduro Evo to Whistler I tightened the 3/4mm bolts up a bit to reduce chainslap, then when I got back home I backed it off for quieter trail riding.

Whenever I remove the T55 I always put a little grease inside to hopefully help keep things moving smoothly.

Oh boy! I'm excited to take it apart and mess with it I bought mine from a online store on eBay. Chances are SRAM won't warranty and I don't want to go through the store I got it from. Turn around times are probably ridiculous. Should have stuck with my 2x10

Just an FYI, I had SRAM warranty mine through my LBS and they actually sent the new derailleur before getting the old one back. The whole process took about a week. The new derailleur clunks a bit, but far less than the old one, so I've just left it alone since I can't feel it while riding.

Just an FYI, I had SRAM warranty mine through my LBS and they actually sent the new derailleur before getting the old one back. The whole process took about a week. The new derailleur clunks a bit, but far less than the old one, so I've just left it alone since I can't feel it while riding.

if i was a SRAM shareholder, i'd be majorly angered how they waste money and good name on this. Somebody at SRAM should clearly be fired. The least they could have done is to release a service manual specifically to fix this issue and making it not lose warranty. Very naive and dumb.

large allen wrench. i don't recall for sure, but i want to say it was a 8mm or 10mm

A 8mm Allen will work.

I took my T55 off, loosened the 3/4 mm Allen's, greased everything and then tightened the 3/4 back up and put it all back together. Now I have no tension on the Derail. I have tightened everything back as tight as it will go and nothing.

I took my T55 off, loosened the 3/4 mm Allen's, greased everything and then tightened the 3/4 back up and put it all back together. Now I have no tension on the Derail. I have tightened everything back as tight as it will go and nothing.

Not sure where to go from here. What a POS.

i'd guess you haven't gone far enough with the T55... maybe!

did you undo and grease the clutch too? (2 parts afaik) could be there's too much grease in it?

I took my T55 off, loosened the 3/4 mm Allen's, greased everything and then tightened the 3/4 back up and put it all back together. Now I have no tension on the Derail. I have tightened everything back as tight as it will go and nothing.

Not sure where to go from here. What a POS.

actually this also sounds like you lost tension on the spring and you haven't re-tension/re-loaded it by one rotation

Think I figured out that the 55mm Torx is simply a plastic cap that supports and locks the inner 4mm hex shaft. That 4mm shaft must apply the resistance for the arm because I backed it out 1/4 turn, it released the knocking/clunking arm and is now quite smooth. The 55mm torx cap I believe is what locks the 4m in place.
What do you think, and have you tried that adjustment, w/o removing everything and re-greasing, and did that work for you?

Think I figured out that the 55mm Torx is simply a plastic cap that supports and locks the inner 4mm hex shaft. That 4mm shaft must apply the resistance for the arm because I backed it out 1/4 turn, it released the knocking/clunking arm and is now quite smooth. The 55mm torx cap I believe is what locks the 4m in place.
What do you think, and have you tried that adjustment, w/o removing everything and re-greasing, and did that work for you?

it's most likely like you are saying (and another person here had pointed out) - I did this some time ago and don't exactly remember if it's the T55 or the screw(s) you gain access to by removing the T55 - but basically just lowering the clutch pressure should fix this in most cases.

it's most likely like you are saying (and another person here had pointed out) - I did this some time ago and don't exactly remember if it's the T55 or the screw(s) you gain access to by removing the T55 - but basically just lowering the clutch pressure should fix this in most cases.

I have the same issue with xx1 and sb66 carbon. Will check first with the dealer if SRAM France has a replacement for this.

I don't believe you have to go to the trouble of complete dis-assembly, just remove the 55mm torx threaded cap and then turn the 4mm hex a 1/4 turn or so to the left, or just enough to loosen the stick-slip feel of the arm. Then replace the 55mm torx to a "snug" fit to retain the position of the 4mm hex. Careful, the 55mm cap is a fine threaded plastic so cross-threading is a definite possibility.

Type 2 Clutch Overhaul

Here's a link to an article on servicing the Type 2 clutch that may help some people out. Even if you're not keen to fully disassemble it yourself, it'll give you a good idea of what's inside.
I did this to my XX1 derailleur around six months ago and haven't heard anything from it since - Slick Honey or Slickolium seems to do a really good job.

Here's a link to an article on servicing the Type 2 clutch that may help some people out. Even if you're not keen to fully disassemble it yourself, it'll give you a good idea of what's inside.
I did this to my XX1 derailleur around six months ago and haven't heard anything from it since - Slick Honey or Slickolium seems to do a really good job.

I warrantied mine and the new one doesn't have anywhere near the tension as my old one. I can actually move this one very easily vs. really having to pull on my first one.

No pops, clunks or pings after 5 rides so far and the chain is staying on and no slap. I wonder if they changed how they are doing the tension?

From what's been suggested above the variability in all of this, it may just be someone in the factory tightening the 4mm too tight on certain ones. Perhaps you just got one that was tensioned properly.